[Bug tree-optimization/47271] gcc-4.6 -O1 -ftree-vectorize removes a test (if), the function generates invalid outputs

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47271

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> 2011-01-12 19:42:38 
UTC ---
It is caused by revision 160030:

http://gcc.gnu.org/ml/gcc-cvs/2010-05/msg01089.html